Yes, you can only get x points per day per account. I does take a bit to get to Gold, maybe 2 months? But one there it's gravy. I suggest 3 to 4 accounts, to make it worthwhile. Any more and you risk MS catching your IP and locking you down.
There's 3 levels, I forget the names maybe Bronze and Silver. I think you get 10 or 20 points a day, until you hit Gold, when you get your 30, plus the few random points they give away each day as well.
For example, on my accounts, I can get 42 points today. 2 for random, 30 for bing, and 10 for mobile searches:
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